Sewing machine feed mechanism



Aug. Z2, 1950 Filed Sept. 25, 1947 H. GERsTElN 2,520,002

SEWING MACHINE FEED MECHAN-ISM 2 Sheets-Sheet 1 INVENTOR.

Aug'. 22, 1950 H. GERSTEIN 2,520,002

l'SEWING MACHINE FEED MECHANISM Filed Sept. 25, 1947 2 Sheets-Sheet v22INVEN TOR.

Patented Aug. 22, 1950 UNITED STATES PATENT OFFICE.

SEWING. MACHDTE FEED MECHANI'SM Harry Gersten, New' York, N. Y.,assigner to Lever Bias Machine Corporation, New York, N. Y., acorporation of New York Applicationseptember 25, 1947, Serial No.776,064

3' Claims. ly

This invention relates to new and useful improvements in machines forjoining sheet material and has especial reference to machines in whichsheet material is: transformed to a tube which may later be run througha cutting machine to become bias-cut material such as tape.

An object of the invention is to provide a simple, durable, efficient,high-speed machine formed of a combination of elements which can beemployed to achieve the end result with a minimum expenditure of timeand effort on the part of the operator and requiring of him the leastskill in manipulating the machine. -v

A further object is to employ a sewing machine which sews without theuse of a lower feed dog and employs instead a floating flexible footwhich permits more rapid operation vof the machine and keeps thematerial under constant control as to the pressure placed thereon duringthe entire operation.

A still further object is to provide a pull-away device disposed on thefar side of the joining or sewing 'point which is operated insynchron-ism with the joining means to continuously pullthe materialwhen it is free of the needle but to exert no pull thereon while theneedle is passing through the goods.

Yet another object is to provide a novel intermittent feed deviceassociated with the joining means, such as the needle.operatingmechanism, so that the material is fed intermittently at highspeed so that it is at rest when the needle is engaging the material sothat the material is under constant regulated tension and the tearing ofthel goods by the needle or the breaking of the needle by the movementof the goods is entirely avoided. Further and more specific objects,features, and advantages will more clearly appear from the 4detailedspecification hereinafter set forth especially when taken in connectionwith the accompanying drawings which illustrate a present preferred formwhich the invention may assume and which form part of the specification.

In brief and general terms, the invention ccmprises the combination,essential-ly, of a floating or flexible foot operated by the joiningdevice and resting on the goods at all times with varying pressure,eliminating the use of a lower feed dog; a pull-away device beyond thejoining point; means to shape and flatten the material beyond thejoining point and before the pullaway device so that the tubularmaterial thus is flattened out before passing through the pullawayrollers to be later wound up'I or otherwise disposed of; means operatedby the joining device, such as the sewing machine, intermittently tooperate the pull-away rollers or device in synchronism with theoperation of the flexible foot so that when the needle is passingthrough the goods, the flexible foot is holding the material tightlyagainst movement and the intermittent feed device is not exerting anypull on the goods, whereas, when the needle is not passing through thegoods the flexible foot is exerting much less ressure on the goods sothat the intermittent feed device which is then Working may pull thematerial past the joining point. This sequence of operations tairesplace at high speed so that the flow of goods though intermittent ispractically continuous, the goods are flattened out and passed throughthe pull-away rollers, the needle is not broken or the goods torn, andonly one pressure foot is employed, which simplifies the mechanism.

The pressure or flexible foot is of the type shown in U. S. Patent No.2,381,817, issued August '1, 1945 to Percy Gardner et al.

The intermittent feed, with novel adaptations, is of the type shown inU. S. patent application Ser. No. 612,447, led August 24, 1945.

The means for shaping the sheet material into somewhat tubular form,joining it, and the pullaway mechanism generally is shown in U. S.Patent No. 2,347,901 issued May 2, 1944.

The combinations ci these known elements, with certain modifications,results in a novel comhination of elements which enables high speedproduction with a minimum of effort and time on the part of the operatorand with minimum damage to the parts running at high speed, and with amuch simpler form of mechanism than has heretofore been used.

The present preferred form which the invention may assume is illustratedin the drawings, oi which,

Fig. 1 is aplan View of a sewing machine with the invention appliedthereto;

Fig. 2 is a partial side elevation, with portions broken away, lookingfrom the left in Fig. 1;

Fig. 3 is a similar View looking from the right in Fig. l.;

Fig. ll is a horizontal section taken on the line 4-4 o Fig. 2;

5 is a vertical section taken on the line 5 5 of Fig. 4; and,

Fig. 6 is a somewhat schematic view of the entire apparatus includingthe pull-away mechanismwhich forms part of the combination.

Referring now merely to the specific form of the invention shown in thedrawings, it is clear that the device includes a sewing or joiningmachine having the usual horizontal arm I with a dependent leg II inwhich reciprocates the usual shaft I2 on the lower end of which is aflexible presser foot generally indicated at I3 and associated inoperation with the needle I4 operated in the usual manner. This presseris of the type and construction shown in the patent mentioned above. Itis used with the sewing of goods and its use does not require a lowerfeedv dog below the needle as is usually the case. generally comprisesan upper plate I5 supported from the shaft I2 and a lower plate I6disposed freely below the upper plate I5 and guided thereon by means ofpins I'I and springs I8 as more in detail described in the abovementioned patent. When the shaft I2 is down the pressure of the plate onthe goods beneath is a maximum and when the shaft is up the pressure isa minimum so that the goods may be advanced under the plate or footwithout lifting the foot entirely therefrom. Thus the synchronism of thefoot is such that when the needle I4 is passing through the goods, thepressure of the foot holds the goods rmly in place and when the needleis withdrawn the pressure is released to permit the movement of thegoods under the inuence of the pull-away mechanism to be described.

- The reciprocation of the vertical shaft I2 is effected by a pin I3thereon in conjunction with a spring 20 surrounding the shaft andbearing against a collar ZI thereon to tend to force the shaft down atall times. The pin is engaged by an arm E2 fixed to the end of ahorizontal shaft 23 which extends parallel to the arm I5 and issupported in spaced bracket members 24 and 25 connected to the arm I6.The other end of shaft 23 is fixed to an oscillatable lever 26 which inits oscillations also oscillates the shaft 23 and therefore the arm 22previously mentioned. The lever 26 at its inner end has a forked shape21 embracing a cam 23 on the main drive shaft 29 which latter is drivenby any suitable source of power in the manner usual to machines 0f thistype. As the main shaft 29 rotates it rotates the cam 28 and this will,it is obvious, cause the oscillation of the lever 26, the shaft 23, andthe arm 22.

The outer end of the lever 26 is provided with an elongated slot 33 inwhich is slidable a bolt 3I having at one end a head 32 and at the otherend a nut 33 which is adjustable on the bolt. The bolt 3i passes throughan opening in the upper end of a link 3.4 and this position of thisupper end of the link is determined by the position of the bolt in theslot 35. The tightening of the nut 33 will the bolt in the desiredposition. 'I'he distance of the upper end of link 34 from theoscillation axis of the lever 26, which is the axis of the shaft 23,determines the amount of throw given to the link 34 by the oscillationof the lever 26. The link 34 at its lower end is pivotally connected toan arm 35 at one end thereof. As seen in Fig. 4, the arm 35 is bored toreceive a hollow sleeve 35 relatively square in cross section and isconnected thereto by a set screw 31. The sleeve is journalled in abracket plate 38 fastened to a base plate 39 resting on the base plateof the machine and'connected thereto in any suitable manner. At theother end of this base plate 39 .-is disposed another vertical bracketplate 40 in the sleeves 36 and 4I is a shaft 42 on one end of which iscarried a, sprocket gear 43. This shaft 42 is connected by a set screw44 to another larger sleeve 45 the inner surface of which is providedwith sloping ball-ways 46 to house balls 4'I backed by springs 48. Theseball-ways 46 are disposed in the surface of the sleeve 45 adjacent theouter Surfaces of the sleeves 36 and 4I previously mentioned. Thisgeneral construction is a well known form. It is clear that when the arm35 is moved or oscillated in one direction, there can be movement ofsleeve 45 and shaft 42 relative to the sleeves 36 and 4 I, but that whenthe oscillation of arm 35 is in the other direction, the sleeves 36, 4I,and 45 are locked together and therefore the shaft 42 will move with thearm 35 and thus the sprocket gear 43 is turned intermittently as isdesired. g

In Fig. 6 a schematic view of the entire apparatus is shown and it isclear that the chain 49 attached to the sprocket gear 43 is in turnconnected to a gear 5i) connected to a roller 5I on a frame 52 overwhich roller the goods passes after being sewed and flattened out. Apressure roller 53 rests upon the roller 5I and is either weighted orpressed thereupon by a spring to create the proper tension between therollers. There ls another gear 55 associated with the roller 5I overwhich passes a chain 56 connecting to a roller gear 5l on a top roller58 which is thereby driven. A pressure roller 59 rests upon the roller58 under proper tension, the4 same-as the roller 53 rests uponthe roller5 I. The goods passes up between the rollers 58 and 59 and thereafter isallowed to drop down into a suitable receptacle for storage or any otherpurpose, which may involve passage to a machine to becut on the bias.Thus as the material is being sewed it is intermittently pulled awayfrom the sewing point as the flexible foot releases the goodsintermittently.- The pull-away action of the intermittent feed deviceshown in Fig. 4 is synchronized with the releasing action of theflexible foot shown in Fig. 3 so that the material moves smoothly andevenly and is never distorted or torn. A

It is thus seen that by the combination of the flexible foot, theintermittent feed device, and the pull-away mechanism, with the simpleeffective and durable mechanism for operating the foot and theintermittent feed in absolute synchronism with absolutely no possibilityof them getting out of synchronism, there has been created a combinationof elements which are separately known but which when combined in thisfashion produce an apparatus which is highly effective and not in knownuse today to produce tubular goods at a high rate of speed and withgreater accuracy and economy. This result is obtained without anymaterial modification of the basic structureof the joining machine andis achieved by the addition thereto of a few simple elements at-,lowcost and which are extremely rugged in operation.

While the invention has been described in detail and with respect to apresent preferred form which the invention may assume, it is not to belimited to such details and forms since many changes and modificationsmay be made in the invention without departing from the spirit andscopeof the invention in its broadest aspects. Hence itisdesired-to.cover any and all forms and modifications of the invention which maycome within the language or scope of any one or more of the appendedclaims.

What I-claim as my invention, is:

1.*In a device of the class described, a `sewing machine having a mainpower shaft, a cam on said shaft, a reciprocatory shaft, a iiexible footsupported on said reciprocatory shaft, a pivoted lever, a fork on saidlever engaging said cam, said lever having a slot in its other end, alink adjustable at one end with respect to said slot, an arm pivoted tothe other end of said link, a ball-bearing unidirectional feed mechanismconnected to said arm, a pull away roller, a sprocket thereon, asprocket on said feed mechanism, a chain connecting said sprocketswhereby said feed mechanism intermittently operates said rollers, ashaft oscillated by said lever, an arm on said oscillated shaft, and apin on said reciprocatable shaft to be engaged by said last mentionedarm to reciprocate said reciprocatable shaft in synchronism with theoscillation of said lever.

2. In a device of the class described, a sewing machine having a mainpower shaft, a Cam on said shaft, a pivoted lever, a fork on said leverengaging said cam` said lever having a slot in its other end, a linkadjustable at one end with respect to said slot, an arm pivoted to theother end of said link, a ball-bearing unidirectional feed mechanismconnected to said arm, a reciprocating shaft having a flexible footsupported thereon, an abutment formed on said reciprocating shaft, anoscillatable shaft having an arm thereon for engagement with saidabutment, said oscillatable shaft being connected to said lever wherebysaid single cam operates the flexible foot and feed mechanism inabsolute synchronism.

3. In a device of the class described, a sewing machine having a mainpower shaft, a cam on said shaft, a pivoted lever, a fork on said leverengaging said cam, an intermittent feed device, means adjustablyconnecting said intermittent feed device to said lever, a reciprocatingshaft having a exible foot supported thereon, an abutment formed on saidreciprocating shaft, an oscillatable shaft having an arm thereon forengagement with said abutment, said oscillatable shaft being connectedto said lever whereby said single cam operates the exible foot andintermittent feed device in absolute synchronism.

HARRY GERSTEIN.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 2,325,643 Weiss Aug. 3, 19432,381,817 Gardner et al. Aug. '7, 1945

